Heat-treating apparatus



lApril 1s, 195o T A, GEN 2,504,198

HEAT TREATING APPARATUS Filed June 22, 1944 s sheets-sheet 1 ws A Tron/15x April 18, 1950 T, A, AGEN 2,504,198

HEAT TREATING APPARATUS IFiled June 22, 1944 5 Sheets-Sheet 2 ggf Els'- INVENTOE THEODOQE A. JGIV,

u HAS ATTGRJVEK April 18, 1950 I T, A JAGEN l '2,504,198

HEAT TREATING APPARATUS Filed June 22, 1944 /Nvf/To. f THEODOQE A JA GEN,

H/S A TTO QNEY 3 Sheets-Sheet 5 Patented 18, 1950 2.504,1 HEAT-Tammo APPARATUS Theodore A. Jagen, Harrison, N. J.,

assigner to General Motors Corporation, Detroit, Mieli., a

corporation of Delaware Application June 22, 1944, Serial 541,577 19 claims. (el. zes-4) This invention relates to heat treating apparatus. An object of the invention is to provide apparatus for automatically heat treating work pieces to harden portions of them while other portions are left soft, the invention pertaining more especially to thin-walled sleeves or bearing race rings which have overhanging lips at the ends to be kept soft while the body or raceway portion is hardened. Another object is to provide improved means for accurately locating the work with respect to a coil which' heats the work by high frequency electro-magnetic induction. Other objects are to provide improved means for supporting the work concentric with the induction coil and for rotating the work smoothly during heating and expansion. Still another object is to provide improved means to transfer work pieces from a source of supply into a definite relation to an Inductor and to eject the work therefrom.

To these ends and'also to improve generally upon apparatus of this character, the invention consists in the various matters hereinafter described and claimed. In its broader aspects the invention is not necessarily limited to the specific construction selected for illustrative purposes in the accompanying drawings in which Fig. l is a plan view of the apparatus, a portion of the supply chute being in section and some details being omitted.

Fig. 2 is a front view of a portion of the apparatus of Fig. 1, a dash pot and associated parts being in section.

Fig. 3 is a sectional view of a lever and associated parts.

Fig. 4 is a sectional view of a work actuating yoke and associated parts.

Fig. 5 is an end view of the work supporting and rotating mechanism, the work actuating yoke, the work centering plates and portions of one pressure roller mounting being in section and the induction coii being omitted.

Fig. 6 is a sectional view of a pressure roller and its support.

Fig. 7 is chiefly a vertical sectional view extending axially of the coil and the work, the portion of the work in heating position being shown in broken lines and the position of the work at a preliminary and subsequent position being shown in full lines.

Fig. 8 is a diagram.

Fig. 9 is a front elevation.

Fig. 10 is an enlarged end view of the brackets which carry the work supporting rollers.

Fig. 11 is an enlarged side view of one of the rollers.

l scale than in other igures of a work piece to larger Each work pieceHA t, prises a thin walled ring or sleeve with uns L tiifhanslns beyond shoulders S. The work pieces \are` piled in a feed chute lo where they are maintained@ peripheral contact with their axes horiznntti, and substantially parallel. They are transferredi laterally or sideways one at a time from the bottom of the chute to place them successively in axial alignment with an externally tapered induction heating coll I2 ready to be pushed endwise or axially into surrounding and concentric relation to the coil. The tapered coil has power leads il at the small end. In the heating position, each work piece is supported and rotated by a pair of driven rollers Il and I6, each roller having a pair of finely knurled humps or crowned portions il affording two point contact with the piece. One roller Il is parallel with the axis of the heating coil and the other roller I8 has its shaft somewhat skewed or tilted so as to urge the work against a locating stop i when the work is seated. Each roll shaft is journalled in bearings in angle brackets Il and n, the latter as shown in Fig. 10 having a notched vertical wall of less height than the other and one bearing opening being lower and nearer the vertical center line to skew the roll shaft It. Hardened inserts 2| near the bearing openings in the bracket 20 resist wear due to movement ,of the work pieces across them. Each roll shaft carries a pinion 22 meshing with a gear 24 fastened to a pulley 26 which is Journalled on the bracket I9 and driven by a belt 28 from a motor I0. The rollers support and rotate the work in a position concentric with the heating coil. Expansion of the piece as it heats may destroy exact concentricity but the heating effect is nevertheless uniform because all parts of the piece move through the same circular path.

The work is urged downwardly against the supporting rollers l l and I6 by a pair of weighted pressure rollers 32 each being crowned and journalled on cone pointed screws 34 carried by a yoke 36 fastened to the lower end of a rod 3l. Each rod is slldable radially in the perforated inner wall 40 of a sectional quenching jacket 42 which surrounds the work in the heating position. The base of the jacket is supported by the brackets I9 and 20 and has the usual piping connections M from a source of quenching liquid supplied under pressure through a control valve. Each rod 38 has its upper end threaded to adjustably receive a weight 48 which will rest on a guide washer il when the work is not in place. Each the quenching jacket. A pin 64 projecting froml the sleeve enters a slot in the rod to prevent the rod from turning in its guides. The weights urge the rods downwardly but are limited by the guide washers 48 so that, when the work is pushed axialLy into heating position on the supporting rollers, the work will engage the crowned surfaces of the supporting rollers and the pressure rollers 82 and lift the rods and weights a short distance. As the piece expands with heating, the pressure rollers will yield upwardly.

Just prior to the pushing of the work axially into heating position, the work is supported and centered by a pair of parallel plates 58 set in a recess of a table 68. To reach this position, the work has been previously pushed laterally or sidewise from the bottom of the feed chute lv by a reciprocating feed bar 60 operating through the bottom oi' the chute and pushing the lowest piece laterally or sidewise into contact with a yieldable stop finger 62 on a bell crank lever 64 which is pivoted at 66 on the slotted top wall of a sloping exit chute 68. The lever 64 has an adjustable stop screw urged against the top of the chute by a coil spring 12. The stop nnger can yield upwardly to let the piece be discharged into the exit chute after the piece has been pushed into Vthe heating position and retracted therefrom after treatment as will appear.

As the piece rests on the parallel plates 68 it is contained in a reciprocating loading yoke 14 having an upper arm 16 and a lower arm 18. A

detachable work retracting finger 80 projectsv downwardly from the upper arm and a work retracting lug 82 projects upwardly from the lower arm, the lower arm lying in the recess between the plates 56. When the yokeis advanced, the finger and the lug can advance idly between the pressure rollers and the supporting rollers respectively, ready to retract the piece from the heating position when the yoke is retracted. To engage and advance the piece axially, a pusher block 84 is fastened to one side of the yoke and has a forwardly projecting lug 86 arranged to engage the lip L of the work piece. Another block 88 is adjustably secured to the opposite side of the yoke and carries a screw 90 in an inclined position. The screw has a flattened end 62 lying in an inclined position where it is arranged to enter inside the lip L and engage the shoulder S of the work. The lug and the screw advance with the yoke to push the piece into heating position. The flattened end 92 of the screw will engage the shoulder S slightly before the lug 86 engages the lip L. The screw thus acts as a locating means against which the work is urged by the above mentioned skewing of the supporting roller I6.

The loading yoke 14 is secured in the forked end of a reciprocating plunger- 64 of rectangular cross section which slides in guide blocks 96 on the table, a plate 95 moving with the plunger to prevent the work pieces from rolling out of the chute prematurely. The plunger is recessed near the middle and pivotally connected at 9 8 to an operating lever |00 which is pivoted at |02 to the table, the lever being swingable between limits fixed by adjustable stop screws |04 on the table. One arm of the lever has a' pivot pin |06 to which a piston rod |08 is secured, the piston rod projecting from an actuating vcylinder |I0 which is pivoted at ||2 to a block on the table. The lever carries a recessed extension member 4 ||4 bolted and dowelled thereto and having a rounded surface near the free end arranged to engage an adjusting screw on a block ||8 fastened to the top of the reciprocating feed bar 60 which is slidable in guide blocks |22.on the table. The feed bar is positively'moved by the lever extension in one direction to retract the bar 5 stop finger 62 yields upwardly through from the bottom of the feed chute thus to let the lowest piece down in front of the feed bar ready for advance into axial alignment with the heating coil. In its retracted position the bar is temporarily latched by an angular latch lever |24 pivoted on the table and having a latching projection |26 adapted to swing in front of a latch plate |28 fastened to the bottom of the feed bar directly below the block ||8. A spring urges the latch lever to latching position, a lug on the latch lever being located to engage a xed pin |32 to limit the swinging movement. In the position shown in Fig. 1, the latch has been tripped by an adjusting screw |34 carried by the enlarged head of a stud |86 mounted vertically in the lever |00 and its extension member ||4.

The feed bar 60 moves in the feeding direction by spring pressure and movement in this direction is slowed down or damped to avoid overfeeding and to provide time for retracting the treated piece into lined therewith. A coiled spring |36 is fastened to one of the guide blocks |22 and to a vertical bar |40 which is rigidly secured to the end of the feed bar. The lower end of the vertical bar is pinned'at |42 to a piston |44 projecting from a cylinder |46 whose head |48 is fastened by a screw |50 to the bottom face of the table. A ball check valve |52 allows air to enter the cylinder freely through a port but prevents the air from escaping. Slow escape of air is controlled by an adjustable throttle valve |54 in an exit port |56. Thus, the lowest untreated piece in the feed chute is advanced slowly and pushed against the previously treated and retract-,ed piece which is thereupon pushed out laterally into the exit chute as the spring pressed the notch in the top of the chute.

The movement of the feed bar 60 causes actuation of a plurality of switches which control the heating cycle. Fastened to the vertical bar |40 is a bent bracket |60 having an adjusting screw |62 arranged to close a normally open switch |64 as the feed bar advances. A cam or bevelled head |66 on the pin |42 is arranged to swing a switch lever |68 t0 close a normally open switch |10. As the feed bar 60 retracts, the upper part of the bracket |60 will close a safety switch |12. The function of these switches will appear from the diagram. A

Referring to the diagram, heating current is supplied to the leads I3 of the induction heating coil I2 from a transformer T and a motor generator set Whenever a switch |14 is closed by its solenoid |18. Quenching uid under pressure is supplied to the quenching jacket 42 whenever a control valve |15 is opened by a solenoid |16. Fluid pressure is directed to the actuating cylinder ||0 under control of a reversing valve |18 which is actuated in one direction by a. solenoid 76 etc., its master switch |84 being closed whenever its solenoid III is energized as by the momentary closing oi' a push ,button switch ill. Thereafter the machine operates automatically without any attention except to keep the feed chute supplied with work pieces.

fAs soon as the master switch |44 is closed, the solenoid |60 is energized and the reversing valve |16 is operated to energize the cylinder III. The loading yoke 14 is thus advanced to push a work piece'W into heating position inside the quenching jacket and surrounding the heating coil |2. Simultaneously the feed bar Il is positively retracted from the feed chute letting a new piece down in front of it, the feed bar 6l then being latched in retracted position by the latch lever |24. The retreat of the feed bar causes the cam |66 to close the switch |16 but this is an idle closing. Ii there is no obstruction to the advance of the work to heating position, the retreatof the feed bar can occur and will close safety switch |12 which is wired in series with the coil of the switch |14. Thus heating current can only come on when the work is properly seated. The timer now controls closing of a heating switch |80 and heating current is supplied for a timed interval to the induction coil. It is desirable to have an overlap of the heat and quench so, before the heating switch opens, the quench control switch |92 closes and the solenoid |16 is thus energized to open its valve |16 and supply quenching fluid to the piece. The heating switchlll then opens while the quenching period continues. The quench control switch |62 then opens and the fluid is allowed time to drain away from the work before the second heating switch |64 closes for a second heating interval, this second interval being shorter than the rst to temperl the piece. The second heating switch then opens and so does the master switch which de-energizes the solenoid |80 so that the valve |18 is reversed by its spring and the cylinder ||6 energized in the reverse direction. The loading yoke 14 is retracted, pulling the piece out of heating position ready to be pushed into the exit chute when the feed bar 60 again advances. The movement of the lever |00 causes release of the latch |24 and the feed bar 60 advances by spring pressure, the advance being slow because of the throttle Valve. A new piece is advanced against the treated piece which is thus pushed laterally into the exit chute. The advance of the feed bar causes the switch |64 to close and the solenoid |16 is thus energized to again open its valve and supply cooling iiuid to the heating coil |2. This is only to prevent heat from accumulating in the coil due to repeated use. The'ad- Vance of the feed bar also causes its cam |66 to close the switch |10 whereby current can ow through the timer coil |86 and close the master switch without necessity for operating the push button switch. The cycle then goes on repeating.

I claim:

1. In apparatus of the character indicated, an induction heating coil and a quenching jacket mounted one within the other and separated radially to provide an annular work-receiving space and spa-ce for work supporting means, a plurality of work supporting rollers mounted between the coil and the jacket to support the work concentric with the coil, the jacket having spray openings within the length of the coil, and means for driving at least one of the rollers to rotate the y 2. In apparatus of the character indicated, an induction heating coil and a quenching jacket A 6 mounted one within the other, the Jacket having spray openings within the length of the coil, a plurality of work supporting rollers mounted between the coil and the jacket, means for driving at least one of the rollers, and a member shiftable axially of the coil to engage and deliver a work piece onto the supporting rollers.

3. In apparatus of the character indicated, an induction heating coil and a quenching Jacket mounted one within the other, the jacket having spray openings within the length of the coll, a plurality of work supporting rollers mounted between the coil and the jacket. a member shiftable axially of the coil to deliver a work piece onto the supporting rollers, and means carried by the member for retracting a treated piece from the rollers.

4. In apparatus of the character indicated. an induction heating coil and a quenching jacket mounted one within the other, the jacket having spray openings within the length of the coil, a plurality of work supporting rollers mounted between the coil and the jacket, a reciprocating member shiftable axially of the coil. the member having means to engage one end portion of a circular work piece to push it onto the rollers. and the member having means extending around to the opposite end portion of the work to retract the work from the rollers.

5. In apparatus of the character indicated, an induction heating coil and a quenching jacket mounted one within the other with an annular space between to receive a ring-shaped work piece, the jacket having spray openings within the length of the coil, work supporting means in the annular space to support the piece concentric with the coil, and a reciprocating device having means to push the work piece onto the supporting means and to retract it therefrom.

6. In apparatus of the character indicated, an induction heating coil and a quenching jacket mounted one within the other with an annular space between to receive a ring-shaped work piece, the jacket having spray openings within the length of the coil, a plurality of work supporting rollers mounted in the annular space, and a pressure roller engaging the work piece at another location and yieldable substantially radially of the piece.

7. In apparatus of the character indicated, an induction heating coil and a quenching jacket mounted one within the other with an annular space between to receive a ring-shaped work piece, a plurality of work supporting rollers fmounted in the annular space, means for pushing the work piece axially along the rollers, and a crowned pressure roller engaging the work piece and yieldable radially.

8. In apparatus of the character indicated, an induction heating coil and a quenching jacket mounted one within the other, a pair of work supporting rollers mounted between the coil and the jacket, a pressure roller engaging the work piece at another location, and a rod slidable in the jacket and supporting the pressure roller for yielding movement substantially radially of the work piece.

9. In apparatus of the character indicated. an induction heating coil and a quenching jacket mounted one within the other, a plurality of work engaging rollers mounted between the coil and the jacket, means for driving at least one of the rollers, means engaging one end of the work piece to locate it axially, and one of the rollers having its axis skewed with respect to the axis o! atomes the coil to urge the work against the locating means.

10. In apparatus of the character indicated. an induction heating coil. a plurality of work supporting rollers spaced radially from the coil to support a ring-shaped work piece concentric with the coil. the rollers and the coil being mounted one outside ci and the other inside of the work piece, and means i'or driving at least one ol the rollers to rotate the piece.

11. In apparatus of the character indicated, an induction heating coil. a pair of work supporting rollers spaced from the coil to support a ringshaped work piece concentric with the coil, one

roller having its axis parallel to the axis of the coil, the other roller having a pair of crowned portions and its axis being skewed, and means for driving at least one o! the rollers to rotate the piece.

12. In apparatus o! the character indicated, an induction heating coil, a pair of work supporting rollers spaced radially outside of the coil to support a ring-shaped work piece concentric with the coil, means for driving at least one of the rollers. and a pressure roller engaging the periphery of the piece at another location and yieldable away from the supporting rollers as the piece expands.

13. In apparatus of the character indicated, an induction heating coil, a pair of work supporting rollers spaced from the coil to support a ringshaped work piece concentric with the coil. at least one of the rollers being driven, one of the rollers having its axis parallel to the axis of the coil and the other rollerv having its axis skewed, and a work locating member to engage an end portion of the work piece and against which the piece is urged by theskewing of the roller.

14. In apparatus of the character indicated, an induction heating coil, a pair of work supporting and work rotating rollers spaced radially from the coil to support a ring-shaped work piece concentric with the coil, spaced centering plates parallel to the axis of the coil, and means for pushing a work piece from the centering plates onto the supporting rollers.

15. In apparatus of the character indicated, an induction heating coil. a pair of work supporting rollers spaced from the coil to support a ringshaped work piece concentric with the coil, spaced centering plates parallel to the axis of the coil, means for pushing a work piece sidewise onto the centering plates. and means for pushing the work piece axially from the centering plates onto the supporting rollers.

16. In apparatus of the character indicated, an induction heating coil, a pair of work supporting rollers spaced from the coil to support a ringshaped work piece concentric with the coil,

axially from the supporting rollers onto the centering plates, and means for moving an untreated piece against the treated piece to eject the latter sidewise from the centering plates.

17. In apparatus o! the character indicated, an induction heating coll. means icr supporting a ring-shaped work piece concentric-with the coil, a pair oi' reciprocating members, one movable axially'oi the coil to convey a work piece to or from the supporting means. the other movable crosswise of the ilrst to bring an untreated piece in line with the coil and expel a treated piece.

18. In apparatus o! the character indicated, an induction heating coll, means for supporting a ring-shaped work piece concentric with the coil. a-pair of reciprocating members. one movable axially of the coil to convey a work piece to or from the supporting means. the other movable crosswise of the rst to bring an untreated piece in line with the coil and expel a treated piece. and means for causing one of said members to move yleldingly in one direction of its movement.

19. In apparatus of the character indicated, an induction heating coil, means for supporting and rotating a ring-shaped work piece concentric with the coil, a reciprocating member, a spring for actuating the member to bring a work piece sidewise into axial alignment with the coil, a dash pot i'or causing said movement to occur slowly. and means for pushing said piece axially of the coil onto the supporting and rotating means.

THEODORE A. JAGEN.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 1,702,985 Twyman Feb. 19, 1929 1,748,465 Summey Feb. 25, 1930 1,782,461 Chapman Nov. 25, 1930 1,808,261 Sessions June 2, 1931 1,877,767 Koch Sept. 20, 1932 2,040,767 Dudley May 12, 1938 2,067,436 Coberly Jan. 12, 1937 2,102,259 Edwards et al Dec. 14, 1937 2,110,632 Mitchell Mar. 8,-1938 '2,202,758 Denneen et al May 28, 1940 2,240,493 Denneen May 6, 1941` 2,280,064 Denneen et al.' Apr. 21, 1942 2,293,534 Denneen et al Aug. 18, 1942 2,329,188 Denneen et al. Sept. 14, 1943 2,359,167 Somes Sept. 26, 1944 2,361,995 Curtis Nov. 7,-1944 2,364,924 Somes Dec. 12, 1944 parallel to the axis ot the 

